<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>集合石之间的关系</title>
</head>

<body>
    <script type="text/javascript">
    function mutation(arr) {
        let arr00 = arr[0].toLowerCase();
        let arr11 = arr[1].toLowerCase();
        for (var i = 0; i < arr11.length; i++) {
            if (arr00.indexOf(arr11[i]) < 0) {
                return false;
            }
            return true;
        }
    }

    mutation(["hello", "hey"]);
    </script>
</body>

</html>